Refrigerating apparatus



Oct; 22, 1935. H T, n-lAlvlaErqLlNU 2,017,947

` REFRIGERATING APPARATUS Original Filed NOV. 30, 1927 Patented Oct. 22, 1935 REFRIGERATING APPARATUS Harry T. Chamberlin, Dayton, Ohio, assignor, by

mesne assignments, to General Motors Corporation, a corporation of Delaware Application November 30, 1927, Serial No. 236,726 Renewed July 25, 1933 23 claims. `(o1. 62-126) This invention relates to improvements in refrigerating elements and more particularly the refrigerating elements used in the production of -cold in mechanically refrigerated cabinets.

It is one of the objects of the invention to provide an improved refrigerating means adapted for use in places where a relatively long, shallow and narrow space is available such as in the display counters used in stores.

More particularly it is an object of the invention to insure proper circulation of refrigerant in a relatively long and narrow refri rating element. Usually a quantity of oil used for lubricating the pumping apparatus is conveyed to the refrigerating element and floats upon the -refrigerant and it is another object of the invention to maintain a uniform stratification of oil and refrigerant in the element so as to obtain substantially uniform evaporation of the refrigerant` throughout the entire length of the element.

In refrigerating elements provided with long circulatory tubes of relatively small bore any accidental bending or kinking of such tubes may result in preventing uniform stratification by causing oil to collect at the damaged portions and to act as a trap to prevent circulation of refrigerant. It is therefore a further object of the invention to use circulatory tubes of relatively large crosssectional area not so readily subject to kinking and to connect the same by a large number of interconnecting ducts, which ducts are used in keeping the stratification uniform.

Further objects and advantages of the present t invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a preferred form of the present invention is clearly shown.

In the drawing:

Fig. 1 shows the improved refrigerating element in side view;

Fig. 2 illustrates a view in section of the same;

Fig. 3 represents an end view in section of the element, and

Fig. '4 is a perspective view of a display counter refrigerator showing the improved element mounted in operative position therein.

Referring in detail to the drawing, the improved refrigerating element comprises a header lil which serves as a container for a refrigerating mediiun which may for example be liquid sulphur dioxide. This header serves to distribute the refrigerant to pipes or ducts hereinafterdef scribed in detail. The refrigerating medium is led into the header by a pipe II and is conducted away therefrom above the liquid level in the header by a pipe I2. A suitable valve I3 controlled by a float I4 is used to control the flow of refrigerant to the header and is adapted to maintain a constant level of liquidin the header.

A series of heat transfer means herein shown las refrigerant circulating ducts or pipes which are formed of a plurality of main ducts interconnected by a large number of loops of pipes are connected to the header in parallel circuit relation as shown in the drawing, Figs. l and 3. 10 The refrigerant circulating ducts are constructed substantially as follows:

Extending longitudinally outward from the end wall of the header and in the samehorizontal plane as the body of the `header are two circulatory ducts. One of these, I5 is of relatively larger size than the other, I6. In the preferred embodiment of `the invention illustrated, the larger duct is disposed above and parallel to the smaller duct. The upper, larger duct terminates in a closed 20 end II while the lower, smaller duct likewise*` terminates in a closed end I8. The two ducts, I5 and I 6. are connected at intervals along their lengths by means of auxiliary interconnecting ducts I9. These interconnecting ducts may be spaced at regular intervals along the lengths of the main ducts as shown or in any other arrangement and are preferably shaped substantially in the form of a horse shoeturned sidewise or U-shaped as shown in Fig. 3. These U- shaped interconnecting ducts are preferably distributed on both sides of the central vertical axis of the ducts I5 and I6 above described.

Each of the interconnecting ducts is provided with a fin 20 of good heat conducting material 35 such as copper which is attached to the duct in good thermal contact as by soldering.

The liquid in the header consists of two components, refrigerant such as liquid sulphur dioxide `and oil which floats on top of the refriger- 40 ant, the result being a stratified effect.

The large duct is connected to the header at a point substantially above the liquid level while the small duct enters the header substantially belowthe liquid level. In operation the stratified liquid passes from the header into the duct I6 and distributes itself in the small duct in the same stratied manner as prevails in the header. The liquid level is shown in Fig. 3. When suction is' applied to the header gaseous refrigerant 50 is withdrawn along with a certain amount of oil.

The oil level and refrigerant level change at times in the header and the same should occur throughout the duct system. This is insured by the vvSystem of interconnecting ducts.

It is obvious that should any of the interconnecting ducts become kinked accidentally it will not materially affect the efficiency of the refrigerating element since sufficient of the remaining ducts will continue functioning to maintain uniform stratification.

Fig. 4 illustrates the improved refrigerating element mounted in a refrigerator of the display case type. In such capacity its function is to serve as a substitute for the ice or brine coils hitherto used for cooling and circulating the air within the case.

In the display case illustrated the case itself comprises an .elongated structure adapted for cooling food stuis while maintaining the same on display. The -case comprises essentially a cabinet which may for example have a rectany gular ground plan. The cabinet may be provided with a plurality of compartments such as a machine or storage compartment and afood display division or compartment 3|. The front 32 of the counter facing the customers may be suitably glazed in the well known manner while the rear may be provided with openings 33 closed by sliding doors or the like. The improved refrigerating element of the invention may be positioned in a compartment 35 in the rear of the display case and so arranged that the refrigerating element will be able to exert its cooling effect upon the goods displayed in the compartment 3|` particularly on the floor 34 thereof.

A baie36 ory deflecting plate is preferably disposed in front of the refrigerating element for producing a proper circulation of cooled air. The compartment 35 therefore` acts after the fashion of a chilling compartment and the baille should accordingly be oiset somewhat from the bottom and top of the case as by means of brackets 31.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

' What is claimed is as follows:

1. Refrigerating means for mechanically refrigerated cabinets comprising an elongated header, a plurality of ducts extending longitudinally from one'end of said header and conduit means providing interconnection between said ducts, said conduit means comprising substantially U-shaped duct loops disposed laterally between said ducts and along their length, said laterally disposed loops being provided with ns transverse to the longitudinal axis of the header and ducts.

2. Refrigerating means for mechanically refrigerated cabinets comprising an elongated header, a plurality of Aducts extending longitudinally from one end of said header and conduit means providing interconnection between said ducts, said conduits means comprising substantially U- shaped duct loops disposed transversely opposite each other on both sides of said ducts, said loops being spaced along the length of said ducts and provided with fins transverse to the longitudinal axis of the header and ducts.

3. Refrigerating means for 'mechanically refrigerated cabinets comprising an elongated header, a plurality of ducts extending longitudinally from one end of said header and having closed ends, one of said ducts comprising a relatively small liquid refrigerant duct and the other a relatively large gas return duct, said ducts being interconnected at intervals along their length by means of transverse duct loops distributed along the length of said ducts, said duct loops being provided with fins transverse to the longitudinal axis of the header and' ducts. 5

4. Refrigerating means for mechanically refrigerated cabinets comprising a reservoir for liquid refrigerant, a plurality of substantially horizontally disposedv ducts connected at one end to the reservoir and disposed one abovel the other, 10 conduit means providing interconnection between said ducts, said conduit means including transverse duct loops disposed on opposite sides of the ducts, and means within the reservoir for maintaining the liquid level below the top of the 15 upper duct.

5. Refrigerating means for mechanically refrigerated cabinets comprising, an elongated horizontally disposed header forming a reservoir for liquid refrigerant, heat exchange means extend- 20 ing horizontally from said reservoir and providing lower liquid refrigerant and upper gas passages interconnected intermediate the ends thereof, and means within .the reservoir for preventing the liquid refrigerant level from rising above 25 a certain level in said heat exchange means.

6. A horizontally disposed evaporator lying in the path of air for directly cooling the air, comprising a finned section forming the greater part ofA the horizontal length of the evaporator and the greater part of the heat absorbing surface of the evaporator, said finned section including a plurality of vertically extending fins and refrigerant carrying heat exchange means thermally connected with said ns for cooling the same, 35 said means providing lower liquid refrigerant and upper gas passages interconnected with one another intermediate the ends thereof, and a reservoir connected with said means for supplying liquid refrigerant to the lower passage and 40 for receiving gaseous refrigerant from the upper passage.

'7. A horizontally disposed evaporator lying in the path of air for directly cooling the air, comprising a finned. section forming the greater 45 part of the horizontal length of the evaporator and the greater part of the heat absorbing surface of the evaporator, said nned section including a plurality of vertically extending ns and refrigerant carrying heat exchange means 50 thermally connected with said ns for cooling the same, said means providing horizontally extending lower liquid refrigerant and upper gas passages and upwardly extending conduit means interconnecting the passages intermediate the 5.5 ends thereof, and a reservoir connected with said means for supplying liquid refrigerant to the lower passage and for receiving gaseous refrigerant from the upper passage.

8.`A horizontally disposed evaporator lying in 00 the path of air for directly cooling the air, cornprising a nned section forming the greater part of the horizontal' length of the evaporator and the greater part of the heat absorbing surface of the evaporator, said nned section including a plurality of vertically extending fins and refrigerant carrying heat exchange means, said means providing horizontally extending lower liquid refrigerant and upper gas passages and outwardly` and upwardly extending conduit means interconnecting the passages intermediate the ends thereof, said extending conduit means being intimately connected with the fins, and a reservoir connected with said means for supplying liquid |15 refrigerant to the lower passage and for receiving gaseous refrigerant from the upperA passage.

9. A horizontally elongated spike-like evap-vl interconnected with one another intermediatethe \ing means adapted for usel in mechanically reends thereof, and a reservoir connected with said heat exchange means for supplying liquid refrigerant to the lower passage and for receiving gaseous refrigerant from the upper passage.

10. A horizontally elongated spike-like evaporator disposed in the path of air for directly cooling the air, comprising a heat transfer section forming 'the greater part of the horizontal length of the evaporator and the greater part of the heat absorbing surface of the evaporator, said section including long horizontally disposed refrigerant conveying tubes providing lower refrigerant and upper gas passages and conduit means interconnecting said tubes intermediate the ends thereof, and a reservoir connected with said heat exchange means for supplying liquid refrigerant to the lower passage and for receiving i gaseous refrigerant from-the upper passage.

11. A relatively long and shallow refrigerating means adapted for use in mechanically refrigerated cabinets `having a long and shallow refrigy erating chamber comprising an elongated and substantially horizontally disposed header, a plurality of ducts extending longitudinally from one end of said header and having closed ends said ducts being disposed at different levels, and conduit means providing interconnection between said ducts, and' means within the header for maintaining the lower duct flooded with liquid refrigerant and for preventing the liquid refrigerant from rising yin the upper duct above a certain level.

12. A relatively long and shallow refrigerating means adapted for use in mechanically refrigerated cabinets-having a long and shallow refrigerating chamber comprising an elongated and substantially horizontally disposed header, a

plurality of ducts extending longitudinally from frigerated cabinets having a long and shallow refrigerating chamber comprising an elongated and substantially horizontally disposed header, a plurality of ducts extending longitudinally from one end of said header said ducts being disposed at different levels, and `conduit means providing interconnection between said ducts, said conduit `means comprising substantially U-shaped duct loops disposed laterally between said ducts and along Vtheir length, and means within the header for maintaining the lower duct flooded with liquid refrigerant and for preventing the liquid refrigerant from rising in the upperduct above a certain level.

frigerated cabinets having a long and shallow refrigerating chamber comprising an elongated and substantially horizontally disposed header, a plurality of ducts extending longitudinally from one end of said header and conduit means providing interconnection between said ducts, said conduit means comprisingsubstantially U- shaped duct loops disposed transversely opposite each other on both sides of said ducts, said loops being spaced along the length of said ducts.

15. A relatively long and shallow refrigerating means adapted for use in mechanically refrigerated cabinets havingl a long and shallow refrigerating chamber comprising an elongated and substantially horizontally disposed header, a' plurality of ducts extending longitudinally from one end of said header and having closed ends,

one of said ducts comprising a lower relatively 20 small liquid refrigerant duct and the other an upper relatively large gas return duct, said ducts being interconnected at intervals along their length, and means within the header for maintaining the lower duct flooded with liquid refrigerant and for preventing the liquid refrigerant from rising in the upper duct above a certain level.

16. A relatively -long and shallow refrigerating means adapted for use in mechanically refrigerated cabinets having a long and shallow refrigerating chamber comprising an elongated and substantially horizontally disposed header, a plurality of ducts extending longitudinally from one end of said headerand having closed ends, one of said ducts comprising a lower relatively small liquid refrigerant duct and the other an upper relatively large gas return duct, said ducts being interconnected at intervals along their length by means of transverse duct loops 40 distributed-along the length of saidducts.

17. Refrigerating means for mechanically refrigerated cabinets comprising a reservoir for liquid refrigerant, a plurality of substantially horizontally extending ducts disposed at diierent levels connected at one end to the reservoir, conduit means interposed between the ends of said ducts providing interconnections between the ducts, and means within the reservoir for maintaining the lower duct flooded with liquid refrigerant, and formaintaining a predetermined level of liquidrefrigerant in the upper duct.

18. Refrigerating meansffor mechanically refrigerated cabinets comprising a reservoir for liquid refrigerant, Aa plurality of substantially horizontally disposed ducts connected at one end tothe reservoir and disposed one above the other, conduit means interposed between the ends of said ducts providing interconnections between the ducts, and means for maintaining a predetermined level of liquid refrigerant in the upper duct.

19. Refrigerating means for mechanically refrigerated` cabinets comprising a reservoir for liquid refrigerant, a plurality of substantially horizontally disposed ducts connected at one end to the reservoir and disposed one above the other, means within the reservoir for maintaining the liquid level in the upper duct below the top thereof, and a plurality of conduits disposed along the length of the ducts for interconnecting same,

said conduits being connected with the upper duct above the liquid level therein. 1' 20. An evaporator for a refrigerating system having means forming an elongated horizontally disposed header, means forming a plurality of substantially parallel refrigerant conveying ducts extending from one end of said header and being disposed one above the other, means forming a plurality of conduits interposed between the ends of said ducts and forming interconnections therebetween, and said conduits having portions thereof extending outwardly from said ducts.

21. An evaporator for a refrigerating system having means forming a plurality of substantially parallel refrigerant conveying ducts disposed one above the other, means connecting at least one end of each of said ducts in communicative relation, means forming a plurality of conduits interposed between the ends of said ducts and forming interconnections therebetween, and said conduits having portions thereof extending outwardly from said ducts.

22. An evaporator for a refrigerating system having means forming a plurality of substantially parallel refrigerant conveying ducts disposed one above the other, means connecting'at least one end of each of said ducts in communicative relation, means forming a plurality of conduits interposed between the ends of said ducts and forming interconnections therebetween, and said conduits being bowed and extending outwardly from each side of said ducts.

23. An evaporator adapted to be positioned in a chamber having relatively low head room comprising, upper and lower headers positioned relatively close together, a plurality of bowed tubes connecting said headers and extending in both directions laterally from the headers to a distance greater than the-distance between the headers to provide a plurality of channels for the passage of refrigerant from the lower to the upper header, substantially as set forth.

HARRY T. CHAMBERLIN. 

